2 * arch/arm/mach-ixp4xx/common-pci.c
4 * IXP4XX PCI routines for all platforms
6 * Maintainer: Deepak Saxena <dsaxena@plexity.net>
8 * Copyright (C) 2002 Intel Corporation.
9 * Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
10 * Copyright (C) 2003-2004 MontaVista Software, Inc.
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/interrupt.h>
23 #include <linux/init.h>
24 #include <linux/ioport.h>
25 #include <linux/slab.h>
26 #include <linux/delay.h>
27 #include <linux/device.h>
29 #include <asm/dma-mapping.h>
31 #include <asm/cputype.h>
33 #include <asm/sizes.h>
34 #include <asm/system.h>
35 #include <asm/mach/pci.h>
36 #include <mach/hardware.h>
40 * IXP4xx PCI read function is dependent on whether we are
41 * running A0 or B0 (AppleGate) silicon.
43 int (*ixp4xx_pci_read
)(u32 addr
, u32 cmd
, u32
* data
);
46 * Base address for PCI regsiter region
48 unsigned long ixp4xx_pci_reg_base
= 0;
51 * PCI cfg an I/O routines are done by programming a
52 * command/byte enable register, and then read/writing
53 * the data from a data regsiter. We need to ensure
54 * these transactions are atomic or we will end up
55 * with corrupt data on the bus or in a driver.
57 static DEFINE_SPINLOCK(ixp4xx_pci_lock
);
60 * Read from PCI config space
62 static void crp_read(u32 ad_cbe
, u32
*data
)
65 spin_lock_irqsave(&ixp4xx_pci_lock
, flags
);
66 *PCI_CRP_AD_CBE
= ad_cbe
;
67 *data
= *PCI_CRP_RDATA
;
68 spin_unlock_irqrestore(&ixp4xx_pci_lock
, flags
);
72 * Write to PCI config space
74 static void crp_write(u32 ad_cbe
, u32 data
)
77 spin_lock_irqsave(&ixp4xx_pci_lock
, flags
);
78 *PCI_CRP_AD_CBE
= CRP_AD_CBE_WRITE
| ad_cbe
;
79 *PCI_CRP_WDATA
= data
;
80 spin_unlock_irqrestore(&ixp4xx_pci_lock
, flags
);
83 static inline int check_master_abort(void)
85 /* check Master Abort bit after access */
86 unsigned long isr
= *PCI_ISR
;
88 if (isr
& PCI_ISR_PFE
) {
89 /* make sure the Master Abort bit is reset */
90 *PCI_ISR
= PCI_ISR_PFE
;
91 pr_debug("%s failed\n", __func__
);
98 int ixp4xx_pci_read_errata(u32 addr
, u32 cmd
, u32
* data
)
104 spin_lock_irqsave(&ixp4xx_pci_lock
, flags
);
109 * PCI workaround - only works if NP PCI space reads have
110 * no side effects!!! Read 8 times. last one will be good.
112 for (i
= 0; i
< 8; i
++) {
114 *data
= *PCI_NP_RDATA
;
115 *data
= *PCI_NP_RDATA
;
118 if(check_master_abort())
121 spin_unlock_irqrestore(&ixp4xx_pci_lock
, flags
);
125 int ixp4xx_pci_read_no_errata(u32 addr
, u32 cmd
, u32
* data
)
130 spin_lock_irqsave(&ixp4xx_pci_lock
, flags
);
134 /* set up and execute the read */
137 /* the result of the read is now in NP_RDATA */
138 *data
= *PCI_NP_RDATA
;
140 if(check_master_abort())
143 spin_unlock_irqrestore(&ixp4xx_pci_lock
, flags
);
147 int ixp4xx_pci_write(u32 addr
, u32 cmd
, u32 data
)
152 spin_lock_irqsave(&ixp4xx_pci_lock
, flags
);
156 /* set up the write */
159 /* execute the write by writing to NP_WDATA */
160 *PCI_NP_WDATA
= data
;
162 if(check_master_abort())
165 spin_unlock_irqrestore(&ixp4xx_pci_lock
, flags
);
169 static u32
ixp4xx_config_addr(u8 bus_num
, u16 devfn
, int where
)
174 addr
= BIT(32-PCI_SLOT(devfn
)) | ((PCI_FUNC(devfn
)) << 8) |
178 addr
= (bus_num
<< 16) | ((PCI_SLOT(devfn
)) << 11) |
179 ((PCI_FUNC(devfn
)) << 8) | (where
& ~3) | 1;
185 * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
186 * 0 and 3 are not valid indexes...
188 static u32 bytemask
[] = {
196 static u32
local_byte_lane_enable_bits(u32 n
, int size
)
199 return (0xf & ~BIT(n
)) << CRP_AD_CBE_BESL
;
201 return (0xf & ~(BIT(n
) | BIT(n
+1))) << CRP_AD_CBE_BESL
;
207 static int local_read_config(int where
, int size
, u32
*value
)
210 pr_debug("local_read_config from %d size %d\n", where
, size
);
212 crp_read(where
& ~3, &data
);
213 *value
= (data
>> (8*n
)) & bytemask
[size
];
214 pr_debug("local_read_config read %#x\n", *value
);
215 return PCIBIOS_SUCCESSFUL
;
218 static int local_write_config(int where
, int size
, u32 value
)
220 u32 n
, byte_enables
, data
;
221 pr_debug("local_write_config %#x to %d size %d\n", value
, where
, size
);
223 byte_enables
= local_byte_lane_enable_bits(n
, size
);
224 if (byte_enables
== 0xffffffff)
225 return PCIBIOS_BAD_REGISTER_NUMBER
;
226 data
= value
<< (8*n
);
227 crp_write((where
& ~3) | byte_enables
, data
);
228 return PCIBIOS_SUCCESSFUL
;
231 static u32
byte_lane_enable_bits(u32 n
, int size
)
234 return (0xf & ~BIT(n
)) << 4;
236 return (0xf & ~(BIT(n
) | BIT(n
+1))) << 4;
242 static int ixp4xx_pci_read_config(struct pci_bus
*bus
, unsigned int devfn
, int where
, int size
, u32
*value
)
244 u32 n
, byte_enables
, addr
, data
;
245 u8 bus_num
= bus
->number
;
247 pr_debug("read_config from %d size %d dev %d:%d:%d\n", where
, size
,
248 bus_num
, PCI_SLOT(devfn
), PCI_FUNC(devfn
));
252 byte_enables
= byte_lane_enable_bits(n
, size
);
253 if (byte_enables
== 0xffffffff)
254 return PCIBIOS_BAD_REGISTER_NUMBER
;
256 addr
= ixp4xx_config_addr(bus_num
, devfn
, where
);
257 if (ixp4xx_pci_read(addr
, byte_enables
| NP_CMD_CONFIGREAD
, &data
))
258 return PCIBIOS_DEVICE_NOT_FOUND
;
260 *value
= (data
>> (8*n
)) & bytemask
[size
];
261 pr_debug("read_config_byte read %#x\n", *value
);
262 return PCIBIOS_SUCCESSFUL
;
265 static int ixp4xx_pci_write_config(struct pci_bus
*bus
, unsigned int devfn
, int where
, int size
, u32 value
)
267 u32 n
, byte_enables
, addr
, data
;
268 u8 bus_num
= bus
->number
;
270 pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value
, where
,
271 size
, bus_num
, PCI_SLOT(devfn
), PCI_FUNC(devfn
));
274 byte_enables
= byte_lane_enable_bits(n
, size
);
275 if (byte_enables
== 0xffffffff)
276 return PCIBIOS_BAD_REGISTER_NUMBER
;
278 addr
= ixp4xx_config_addr(bus_num
, devfn
, where
);
279 data
= value
<< (8*n
);
280 if (ixp4xx_pci_write(addr
, byte_enables
| NP_CMD_CONFIGWRITE
, data
))
281 return PCIBIOS_DEVICE_NOT_FOUND
;
283 return PCIBIOS_SUCCESSFUL
;
286 struct pci_ops ixp4xx_ops
= {
287 .read
= ixp4xx_pci_read_config
,
288 .write
= ixp4xx_pci_write_config
,
294 static int abort_handler(unsigned long addr
, unsigned int fsr
, struct pt_regs
*regs
)
299 local_read_config(PCI_STATUS
, 2, &status
);
300 pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
301 "status = %#x\n", addr
, isr
, status
);
303 /* make sure the Master Abort bit is reset */
304 *PCI_ISR
= PCI_ISR_PFE
;
305 status
|= PCI_STATUS_REC_MASTER_ABORT
;
306 local_write_config(PCI_STATUS
, 2, status
);
309 * If it was an imprecise abort, then we need to correct the
310 * return address to be _after_ the instruction.
320 * Setup DMA mask to 64MB on PCI devices. Ignore all other devices.
322 static int ixp4xx_pci_platform_notify(struct device
*dev
)
324 if(dev
->bus
== &pci_bus_type
) {
325 *dev
->dma_mask
= SZ_64M
- 1;
326 dev
->coherent_dma_mask
= SZ_64M
- 1;
327 dmabounce_register_dev(dev
, 2048, 4096);
332 static int ixp4xx_pci_platform_notify_remove(struct device
*dev
)
334 if(dev
->bus
== &pci_bus_type
) {
335 dmabounce_unregister_dev(dev
);
340 int dma_needs_bounce(struct device
*dev
, dma_addr_t dma_addr
, size_t size
)
342 return (dev
->bus
== &pci_bus_type
) && ((dma_addr
+ size
) >= SZ_64M
);
346 * Only first 64MB of memory can be accessed via PCI.
347 * We use GFP_DMA to allocate safe buffers to do map/unmap.
348 * This is really ugly and we need a better way of specifying
349 * DMA-capable regions of memory.
351 void __init
ixp4xx_adjust_zones(int node
, unsigned long *zone_size
,
352 unsigned long *zhole_size
)
354 unsigned int sz
= SZ_64M
>> PAGE_SHIFT
;
357 * Only adjust if > 64M on current system
359 if (node
|| (zone_size
[0] <= sz
))
362 zone_size
[1] = zone_size
[0] - sz
;
364 zhole_size
[1] = zhole_size
[0];
368 void __init
ixp4xx_pci_preinit(void)
370 unsigned long cpuid
= read_cpuid_id();
373 * Determine which PCI read method to use.
374 * Rev 0 IXP425 requires workaround.
376 if (!(cpuid
& 0xf) && cpu_is_ixp42x()) {
377 printk("PCI: IXP42x A0 silicon detected - "
378 "PCI Non-Prefetch Workaround Enabled\n");
379 ixp4xx_pci_read
= ixp4xx_pci_read_errata
;
381 ixp4xx_pci_read
= ixp4xx_pci_read_no_errata
;
384 /* hook in our fault handler for PCI errors */
385 hook_fault_code(16+6, abort_handler
, SIGBUS
, "imprecise external abort");
387 pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
390 * We use identity AHB->PCI address translation
391 * in the 0x48000000 to 0x4bffffff address space
393 *PCI_PCIMEMBASE
= 0x48494A4B;
396 * We also use identity PCI->AHB address translation
397 * in 4 16MB BARs that begin at the physical memory start
399 *PCI_AHBMEMBASE
= (PHYS_OFFSET
& 0xFF000000) +
400 ((PHYS_OFFSET
& 0xFF000000) >> 8) +
401 ((PHYS_OFFSET
& 0xFF000000) >> 16) +
402 ((PHYS_OFFSET
& 0xFF000000) >> 24) +
405 if (*PCI_CSR
& PCI_CSR_HOST
) {
406 printk("PCI: IXP4xx is host\n");
408 pr_debug("setup BARs in controller\n");
411 * We configure the PCI inbound memory windows to be
412 * 1:1 mapped to SDRAM
414 local_write_config(PCI_BASE_ADDRESS_0
, 4, PHYS_OFFSET
);
415 local_write_config(PCI_BASE_ADDRESS_1
, 4, PHYS_OFFSET
+ SZ_16M
);
416 local_write_config(PCI_BASE_ADDRESS_2
, 4, PHYS_OFFSET
+ SZ_32M
);
417 local_write_config(PCI_BASE_ADDRESS_3
, 4, PHYS_OFFSET
+ SZ_48M
);
420 * Enable CSR window at 64 MiB to allow PCI masters
421 * to continue prefetching past 64 MiB boundary.
423 local_write_config(PCI_BASE_ADDRESS_4
, 4, PHYS_OFFSET
+ SZ_64M
);
426 * Enable the IO window to be way up high, at 0xfffffc00
428 local_write_config(PCI_BASE_ADDRESS_5
, 4, 0xfffffc01);
430 printk("PCI: IXP4xx is target - No bus scan performed\n");
433 printk("PCI: IXP4xx Using %s access for memory space\n",
434 #ifndef CONFIG_IXP4XX_INDIRECT_PCI
441 pr_debug("clear error bits in ISR\n");
442 *PCI_ISR
= PCI_ISR_PSE
| PCI_ISR_PFE
| PCI_ISR_PPE
| PCI_ISR_AHBE
;
445 * Set Initialize Complete in PCI Control Register: allow IXP4XX to
446 * respond to PCI configuration cycles. Specify that the AHB bus is
447 * operating in big endian mode. Set up byte lane swapping between
448 * little-endian PCI and the big-endian AHB bus
451 *PCI_CSR
= PCI_CSR_IC
| PCI_CSR_ABE
| PCI_CSR_PDS
| PCI_CSR_ADS
;
453 *PCI_CSR
= PCI_CSR_IC
| PCI_CSR_ABE
;
459 int ixp4xx_setup(int nr
, struct pci_sys_data
*sys
)
461 struct resource
*res
;
466 res
= kzalloc(sizeof(*res
) * 2, GFP_KERNEL
);
469 * If we're out of memory this early, something is wrong,
470 * so we might as well catch it here.
472 panic("PCI: unable to allocate resources?\n");
475 local_write_config(PCI_COMMAND
, 2, PCI_COMMAND_MASTER
| PCI_COMMAND_MEMORY
);
477 res
[0].name
= "PCI I/O Space";
478 res
[0].start
= 0x00000000;
479 res
[0].end
= 0x0000ffff;
480 res
[0].flags
= IORESOURCE_IO
;
482 res
[1].name
= "PCI Memory Space";
483 res
[1].start
= PCIBIOS_MIN_MEM
;
484 res
[1].end
= PCIBIOS_MAX_MEM
;
485 res
[1].flags
= IORESOURCE_MEM
;
487 request_resource(&ioport_resource
, &res
[0]);
488 request_resource(&iomem_resource
, &res
[1]);
490 sys
->resource
[0] = &res
[0];
491 sys
->resource
[1] = &res
[1];
492 sys
->resource
[2] = NULL
;
494 platform_notify
= ixp4xx_pci_platform_notify
;
495 platform_notify_remove
= ixp4xx_pci_platform_notify_remove
;
500 struct pci_bus
* __devinit
ixp4xx_scan_bus(int nr
, struct pci_sys_data
*sys
)
502 return pci_scan_bus(sys
->busnr
, &ixp4xx_ops
, sys
);
506 * We override these so we properly do dmabounce otherwise drivers
507 * are able to set the dma_mask to 0xffffffff and we can no longer
510 * We just return true on everyhing except for < 64MB in which case
511 * we will fail miseralby and die since we can't handle that case.
514 pci_set_dma_mask(struct pci_dev
*dev
, u64 mask
)
516 if (mask
>= SZ_64M
- 1 )
523 pci_set_consistent_dma_mask(struct pci_dev
*dev
, u64 mask
)
525 if (mask
>= SZ_64M
- 1 )
531 EXPORT_SYMBOL(ixp4xx_pci_read
);
532 EXPORT_SYMBOL(ixp4xx_pci_write
);